'In the daytime he led them with a cloud, and all night long with a fiery light.'

nuance |ˈnjuːɑːns|
noun
a subtle difference in or shade of meaning, expression, or sound : the nuances of facial expression and body language.
ORIGIN late 18th cent.: from French, ‘shade, subtlety,’ from nuer ‘to shade,’ based on Latin nubes ‘cloud.’

cloud |klaʊd|
noun
a visible mass of condensed water vapor floating in the atmosphere, typically high above the ground : the sun had disappeared behind a cloud | the full moon, hidden by veils of cloud.
ORIGIN Old English clūd [mass of rock or earth] ; probably related to clot.

clot |klɒt|
noun
a thick mass of coagulated liquid, esp. blood, or of material stuck together : a flat, wet clot of dead leaves | figurative: a clot of people arguing in the doorway.
ORIGIN Old English clott, clot, of Germanic origin; related to Yiddish klutz [foolish person]